What should come in place of the question mark '?' in the following number series?
40, 10, 50, 12.5, ?, 15.625
1
60.5
2
64.5
3
65
4
45
5
62.5
What should come in place of the question mark '?' in the following number series?
40, 10, 50, 12.5, ?, 15.625